org.eclipse.swt.accessibility
Class AccessibleControlAdapter

java.lang.Object
  org.eclipse.swt.accessibility.AccessibleControlAdapter

All Implemented Interfaces:

AccessibleControlListener

public abstract class AccessibleControlAdapter

extends Object

implements AccessibleControlListener

This adapter class provides default implementations for the methods described by the AccessibleControlListener interface.

Classes that wish to deal with AccessibleControlEvents can extend this class and override only the methods that they are interested in.

Note: Accessibility clients use child identifiers to specify whether they want information about a control or one of its children. Child identifiers are increasing integers beginning with 0. The identifier CHILDID_SELF represents the control itself. When returning a child identifier to a client, you may use CHILDID_NONE to indicate that no child or control has the required information.

Note: This adapter is typically used by implementors of a custom control to provide very detailed information about the control instance to accessibility clients.

Since:

1.4

See Also:

AccessibleControlListener, AccessibleControlEvent, Sample code and further information

Constructor Summary

AccessibleControlAdapter()

Method Summary

void	getChild(AccessibleControlEvent e) Sent when an accessibility client requests the accessible object for a child of the control by index or childID, or when a client requests the index of an accessible object in its parent.
void	getChildAtPoint(AccessibleControlEvent e) Sent when an accessibility client requests the identifier of the control child at the specified display coordinates.
void	getChildCount(AccessibleControlEvent e) Sent when an accessibility client requests the number of children in the control.
void	getChildren(AccessibleControlEvent e) Sent when an accessibility client requests the children, or visible children, of the control.
void	getDefaultAction(AccessibleControlEvent e) Sent when an accessibility client requests the default action of the control, or the default action of a child of the control.
void	getFocus(AccessibleControlEvent e) Sent when an accessibility client requests the identity of the child or control that has keyboard focus.
void	getLocation(AccessibleControlEvent e) Sent when an accessibility client requests the location of the control, or the location of a child of the control.
void	getRole(AccessibleControlEvent e) Sent when an accessibility client requests the role of the control, or the role of a child of the control.
void	getSelection(AccessibleControlEvent e) Sent when an accessibility client requests the identity of the child or control that is currently selected.
void	getState(AccessibleControlEvent e) Sent when an accessibility client requests the state of the control, or the state of a child of the control.
void	getValue(AccessibleControlEvent e) Sent when an accessibility client requests the value of the control, or the value of a child of the control.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AccessibleControlAdapter

public AccessibleControlAdapter()

Method Detail

getChildAtPoint

public void getChildAtPoint(AccessibleControlEvent e)

Sent when an accessibility client requests the identifier of the control child at the specified display coordinates. The default behavior is to do nothing.

Return the identifier of the child at display point (x, y) in the childID field of the event object. Return CHILDID_SELF if point (x, y) is in the control itself and not in any child. Return CHILDID_NONE if point (x, y) is not contained in either the control or any of its children.

Specified by:

getChildAtPoint in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• x, y [IN] - the specified point in display coordinates
• childID [Typical OUT] - the ID of the child at point, or CHILDID_SELF, or CHILDID_NONE
• accessible [Optional OUT] - the accessible object for the control or child may be returned instead of the childID

getLocation

public void getLocation(AccessibleControlEvent e)

Sent when an accessibility client requests the location of the control, or the location of a child of the control. The default behavior is to do nothing.

Return a rectangle describing the location of the specified control or child in the x, y, width, and height fields of the event object.

Specified by:

getLocation in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [IN] - an identifier specifying the control or one of its children
• x, y, width, height [OUT] - the control or child location in display coordinates

getChild

public void getChild(AccessibleControlEvent e)

Sent when an accessibility client requests the accessible object for a child of the control by index or childID, or when a client requests the index of an accessible object in its parent.

The childID field in the event object can be one of the following:

• an integer child ID - return the accessible object for the specified child ID, or null if the specified child does not have its own accessible
• ACC.CHILDID_CHILD_AT_INDEX - return the accessible child object at the specified index, or null if this object has no children
• ACC.CHILDID_CHILD_INDEX - return the index of this accessible in its parent

Specified by:

getChild in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [IN] - an identifier specifying a child of the control, or one of the predefined CHILDID constants
• detail [Optional IN] - the index of the child accessible to be returned when childID = CHILDID_CHILD_AT_INDEX
• detail [Optional OUT] - the index of this accessible in its parent when childID = CHILDID_CHILD_INDEX
• accessible [Optional OUT] - an Accessible for the specified childID or index, or null if one does not exist

getChildCount

public void getChildCount(AccessibleControlEvent e)

Sent when an accessibility client requests the number of children in the control. The default behavior is to do nothing.

Return the number of child items in the detail field of the event object.

Specified by:

getChildCount in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• detail [OUT] - the number of child items in this control

getDefaultAction

public void getDefaultAction(AccessibleControlEvent e)

Sent when an accessibility client requests the default action of the control, or the default action of a child of the control. The default behavior is to do nothing.

This string is typically a verb describing what the user does to it. For example, a Push Button's default action is "Press", a Check Button's is "Check" or "UnCheck", and List items have the default action "Double Click".

Return a string describing the default action of the specified control or child in the result field of the event object. Returning null tells the client to use the platform default action string.

Specified by:

getDefaultAction in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [IN] - an identifier specifying the control or one of its children
• result [OUT] - the requested default action string, or null

getFocus

public void getFocus(AccessibleControlEvent e)

Sent when an accessibility client requests the identity of the child or control that has keyboard focus. The default behavior is to do nothing.

Return the identifier of the child that has focus in the childID field of the event object. Return CHILDID_SELF if the control itself has keyboard focus. Return CHILDID_NONE if neither the control nor any of its children has focus.

Specified by:

getFocus in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [Typical OUT] - the ID of the child with focus, or CHILDID_SELF, or CHILDID_NONE
• accessible [Optional OUT] - the accessible object for a child may be returned instead of its childID

getRole

public void getRole(AccessibleControlEvent e)

Sent when an accessibility client requests the role of the control, or the role of a child of the control. The default behavior is to do nothing.

Return a role constant (constant defined in ACC beginning with ROLE_) that describes the role of the specified control or child in the detail field of the event object.

Specified by:

getRole in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [IN] - an identifier specifying the control or one of its children
• detail [OUT] - a role constant describing the role of the control or child

getSelection

public void getSelection(AccessibleControlEvent e)

Sent when an accessibility client requests the identity of the child or control that is currently selected. The default behavior is to do nothing.

Return the identifier of the selected child in the childID field of the event object. Return CHILDID_SELF if the control itself is selected. Return CHILDID_MULTIPLE if multiple children are selected, and return an array of childIDs in the children field. Return CHILDID_NONE if neither the control nor any of its children are selected.

Specified by:

getSelection in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [Typical OUT] - the ID of the selected child, or CHILDID_SELF, or CHILDID_MULTIPLE, or CHILDID_NONE
• children [Optional OUT] - the array of childIDs for the selected children if CHILDID_MULTIPLE is returned
• accessible [Optional OUT] - the accessible object for the control or child may be returned instead of the childID

getState

public void getState(AccessibleControlEvent e)

Sent when an accessibility client requests the state of the control, or the state of a child of the control. The default behavior is to do nothing.

Return a state mask (mask bit constants defined in ACC beginning with STATE_) that describes the current state of the specified control or child in the detail field of the event object.

Specified by:

getState in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [IN] - an identifier specifying the control or one of its children
• detail [OUT] - a state mask describing the current state of the control or child

getValue

public void getValue(AccessibleControlEvent e)

Sent when an accessibility client requests the value of the control, or the value of a child of the control. The default behavior is to do nothing.

Many controls do not return a value. Examples of controls that do are: Combo returns the text string, Text returns its contents, ProgressBar returns a string representing a percentage, and Tree items return a string representing their level in the tree.

Return a string describing the value of the specified control or child in the result field of the event object. Returning null tells the client to use the platform value string.

Specified by:

getValue in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• childID [IN] - an identifier specifying the control or one of its children
• result [OUT] - the requested value string, or null

getChildren

public void getChildren(AccessibleControlEvent e)

Sent when an accessibility client requests the children, or visible children, of the control. The default behavior is to do nothing.

Return the children as an array of childIDs or accessibles in the children field of the event object.

Specified by:

getChildren in interface AccessibleControlListener

Parameters:

e - an event object containing the following fields:

• detail [IN] - a flag that may have one of the following values:
  • 0 (default) - return all children
  • VISIBLE - return all visible children
• children [Typical OUT] - an array of childIDs
• children [Optional OUT] - an array of accessible objects for the children may be returned instead of the childIDs